organic compounds
(1S*,2S*,5R*,8S*,11S*,14R*,17S*,20R*)-14-Methyl-6-methylene-10,16,18-trioxahexacyclo[12.5.1.15,8.01,11.02,8.017,20]henicosane-7,9-dione: natural diterpenoid macrocalyxoformin B
aThe College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
*Correspondence e-mail: shihao@126.com
The title compound, C20H24O5, isolated from Rabdosia var. lophanthoides Hara, is built up from six fused rings. Cyclohexane ring A adopts a chair conformation, ring B exists in a screw-boat conformation and ring C adopts a boat conformation; the three five-membered rings D, E and F adopt envelope conformations.
Related literature
For related literature, see: Wang et al. (1986). For ring puckering parameters, see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection: SMART (Bruker, 1999); cell SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536807060692/dn2278sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807060692/dn2278Isup2.hkl
The title compound (I) was isolated from Rabdosia var lophanthoides Hara and crystals suitable for X-ray structure analysis were obtained by slow evaporation from a solution of methanol at room temperature.
All H atoms were fixed geometrically and treated as riding with C—H = 0.93 Å (=CH2); 0.96 Å (methy), 0.97 Å(methylene) or 0.98 Å (methine) with Uiso(H) = 1.2Ueq(=CH2, methylene, methine) or Uiso(H) = 1.5Ueq(methyl).
In the absence of significant
the could not be reliably determined from the X-ray analyses and the Friedel pairs were merged, relative stereochemistry is shown in the Scheme and figures.The diterpenoid macrocalyxoformin B, (I), has been previously isolated from Rabdosia macrocalyx Hara (Wang et al., 1986) and its structure was established from the spectroscopic and chemical evidence. Recently, it was for the first time isolated from Rabdosia var lophanthoides Hara, and its structure was confirmed by an X-ray diffraction study.
The molecule is built up from six fused rings, three six membered and three five membered rings (Fig. 1). Some geometrical features of these rings were investigated using PLATON (Spek, 2003).
Cyclohexane ring A (C1/C11—C14/C20) adopts a chair conformation (Cremer & Pople, 1975), ring B (O10/C9/C8/C2/C1/C11) exists in a screw-boat conformation, ring C (C2—C5/C21/C8) adopts the boat conformation. All the three five-membered rings adopt envelope conformation.
For related literature, see: Wang et al. (1986). For ring puckering parameters, see: Cremer & Pople (1975).
Data collection: SMART (Bruker, 1999); cell
SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).C20H24O5 | F(000) = 736 |
Mr = 344.39 | Dx = 1.372 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 1585 reflections |
a = 7.845 (1) Å | θ = 2.5–24.9° |
b = 13.1365 (17) Å | µ = 0.10 mm−1 |
c = 16.178 (2) Å | T = 298 K |
V = 1667.2 (4) Å3 | Plate, colorless |
Z = 4 | 0.20 × 0.18 × 0.13 mm |
Bruker SMART CCD area-detector diffractometer | 1707 independent reflections |
Radiation source: fine-focus sealed tube | 1158 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.151 |
φ and ω scans | θmax = 25.0°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | h = −8→9 |
Tmin = 0.981, Tmax = 0.987 | k = −9→15 |
7324 measured reflections | l = −19→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.062 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.159 | H-atom parameters constrained |
S = 0.99 | w = 1/[σ2(Fo2) + (0.0846P)2] where P = (Fo2 + 2Fc2)/3 |
1707 reflections | (Δ/σ)max = 0.001 |
228 parameters | Δρmax = 0.27 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C20H24O5 | V = 1667.2 (4) Å3 |
Mr = 344.39 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.845 (1) Å | µ = 0.10 mm−1 |
b = 13.1365 (17) Å | T = 298 K |
c = 16.178 (2) Å | 0.20 × 0.18 × 0.13 mm |
Bruker SMART CCD area-detector diffractometer | 1707 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | 1158 reflections with I > 2σ(I) |
Tmin = 0.981, Tmax = 0.987 | Rint = 0.151 |
7324 measured reflections |
R[F2 > 2σ(F2)] = 0.062 | 0 restraints |
wR(F2) = 0.159 | H-atom parameters constrained |
S = 0.99 | Δρmax = 0.27 e Å−3 |
1707 reflections | Δρmin = −0.23 e Å−3 |
228 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2722 (6) | 0.1295 (3) | 0.8777 (3) | 0.0774 (13) | |
O2 | 0.1286 (5) | 0.3379 (3) | 0.8514 (2) | 0.0648 (11) | |
O10 | 0.5239 (5) | 0.1278 (3) | 0.8173 (2) | 0.0528 (10) | |
O16 | 0.6881 (4) | 0.3328 (3) | 0.54354 (19) | 0.0531 (10) | |
O18 | 0.4526 (4) | 0.3456 (3) | 0.6322 (2) | 0.0485 (9) | |
C1 | 0.6034 (6) | 0.2829 (4) | 0.7468 (3) | 0.0374 (11) | |
C2 | 0.5314 (6) | 0.3540 (4) | 0.8156 (3) | 0.0403 (12) | |
H2 | 0.4508 | 0.4005 | 0.7890 | 0.048* | |
C3 | 0.6638 (7) | 0.4202 (4) | 0.8615 (3) | 0.0517 (14) | |
H3A | 0.7590 | 0.3776 | 0.8779 | 0.062* | |
H3B | 0.7069 | 0.4715 | 0.8238 | 0.062* | |
C4 | 0.5914 (7) | 0.4733 (4) | 0.9387 (3) | 0.0528 (14) | |
H4A | 0.5317 | 0.5345 | 0.9217 | 0.063* | |
H4B | 0.6853 | 0.4937 | 0.9740 | 0.063* | |
C5 | 0.4682 (7) | 0.4057 (4) | 0.9889 (3) | 0.0490 (14) | |
H5 | 0.4809 | 0.4174 | 1.0485 | 0.059* | |
C6 | 0.2874 (7) | 0.4183 (4) | 0.9622 (3) | 0.0475 (13) | |
C7 | 0.2569 (7) | 0.3448 (4) | 0.8912 (3) | 0.0443 (12) | |
C8 | 0.4269 (6) | 0.2882 (4) | 0.8792 (3) | 0.0421 (12) | |
C9 | 0.3966 (7) | 0.1760 (4) | 0.8572 (3) | 0.0510 (14) | |
C11 | 0.6700 (7) | 0.1866 (4) | 0.7881 (3) | 0.0427 (12) | |
H11 | 0.7402 | 0.2059 | 0.8357 | 0.051* | |
C12 | 0.7723 (7) | 0.1176 (4) | 0.7328 (3) | 0.0523 (14) | |
H12A | 0.7007 | 0.0926 | 0.6883 | 0.063* | |
H12B | 0.8129 | 0.0596 | 0.7642 | 0.063* | |
C13 | 0.9228 (7) | 0.1754 (5) | 0.6971 (3) | 0.0547 (15) | |
H13A | 0.9869 | 0.1302 | 0.6613 | 0.066* | |
H13B | 0.9972 | 0.1962 | 0.7418 | 0.066* | |
C14 | 0.8695 (6) | 0.2705 (4) | 0.6473 (3) | 0.0439 (13) | |
C15 | 0.7866 (7) | 0.2448 (4) | 0.5647 (3) | 0.0542 (15) | |
H15A | 0.8725 | 0.2315 | 0.5230 | 0.065* | |
H15B | 0.7140 | 0.1853 | 0.5699 | 0.065* | |
C17 | 0.6237 (7) | 0.3750 (4) | 0.6172 (3) | 0.0442 (12) | |
H17 | 0.6306 | 0.4494 | 0.6142 | 0.053* | |
C19 | 0.4542 (7) | 0.2586 (4) | 0.6866 (3) | 0.0437 (12) | |
H19A | 0.4755 | 0.1963 | 0.6562 | 0.052* | |
H19B | 0.3471 | 0.2523 | 0.7162 | 0.052* | |
C20 | 0.7337 (6) | 0.3367 (4) | 0.6893 (3) | 0.0400 (11) | |
H20 | 0.7872 | 0.3941 | 0.7180 | 0.048* | |
C21 | 0.5012 (7) | 0.2938 (4) | 0.9666 (3) | 0.0483 (13) | |
H21A | 0.6221 | 0.2782 | 0.9668 | 0.058* | |
H21B | 0.4425 | 0.2480 | 1.0041 | 0.058* | |
C22 | 0.1647 (7) | 0.4771 (5) | 0.9914 (4) | 0.0605 (16) | |
H22A | 0.1859 | 0.5197 | 1.0361 | 0.073* | |
H22B | 0.0572 | 0.4758 | 0.9672 | 0.073* | |
C23 | 1.0269 (7) | 0.3360 (5) | 0.6295 (3) | 0.0599 (15) | |
H23A | 1.1118 | 0.2954 | 0.6023 | 0.090* | |
H23B | 1.0722 | 0.3616 | 0.6806 | 0.090* | |
H23C | 0.9955 | 0.3920 | 0.5945 | 0.090* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.091 (3) | 0.042 (2) | 0.099 (3) | −0.013 (2) | 0.041 (3) | −0.008 (2) |
O2 | 0.057 (2) | 0.072 (3) | 0.065 (2) | 0.008 (2) | −0.006 (2) | −0.013 (2) |
O10 | 0.071 (2) | 0.0318 (19) | 0.0556 (19) | 0.0020 (19) | 0.017 (2) | 0.0054 (17) |
O16 | 0.067 (2) | 0.058 (2) | 0.0344 (17) | 0.002 (2) | 0.0020 (17) | 0.0028 (17) |
O18 | 0.049 (2) | 0.051 (2) | 0.0454 (18) | 0.0031 (19) | −0.0048 (17) | 0.0100 (17) |
C1 | 0.047 (3) | 0.031 (3) | 0.034 (2) | 0.001 (2) | 0.001 (2) | −0.001 (2) |
C2 | 0.049 (3) | 0.034 (3) | 0.038 (2) | 0.002 (2) | 0.001 (2) | −0.001 (2) |
C3 | 0.061 (3) | 0.047 (3) | 0.048 (3) | −0.009 (3) | 0.004 (3) | −0.009 (3) |
C4 | 0.064 (3) | 0.047 (3) | 0.047 (3) | 0.000 (3) | −0.003 (3) | −0.011 (3) |
C5 | 0.063 (3) | 0.048 (3) | 0.036 (2) | 0.004 (3) | −0.001 (3) | −0.004 (2) |
C6 | 0.064 (3) | 0.039 (3) | 0.039 (3) | 0.002 (3) | 0.008 (3) | 0.001 (2) |
C7 | 0.047 (3) | 0.046 (3) | 0.040 (2) | 0.001 (3) | 0.001 (2) | 0.007 (2) |
C8 | 0.054 (3) | 0.033 (3) | 0.039 (3) | 0.003 (2) | 0.006 (2) | −0.001 (2) |
C9 | 0.067 (4) | 0.039 (3) | 0.047 (3) | 0.002 (3) | 0.014 (3) | 0.006 (3) |
C11 | 0.052 (3) | 0.036 (3) | 0.040 (2) | 0.005 (3) | 0.000 (2) | 0.002 (2) |
C12 | 0.063 (3) | 0.039 (3) | 0.055 (3) | 0.014 (3) | 0.008 (3) | 0.001 (2) |
C13 | 0.058 (3) | 0.054 (4) | 0.052 (3) | 0.014 (3) | −0.001 (3) | −0.008 (3) |
C14 | 0.045 (3) | 0.047 (3) | 0.040 (2) | 0.001 (3) | 0.004 (2) | −0.003 (2) |
C15 | 0.065 (4) | 0.054 (4) | 0.044 (3) | 0.008 (3) | 0.006 (3) | −0.005 (3) |
C17 | 0.050 (3) | 0.044 (3) | 0.039 (3) | −0.004 (3) | −0.002 (2) | −0.002 (2) |
C19 | 0.059 (3) | 0.033 (3) | 0.039 (2) | −0.003 (3) | 0.005 (3) | 0.002 (2) |
C20 | 0.049 (3) | 0.036 (3) | 0.035 (2) | −0.003 (2) | 0.002 (2) | 0.002 (2) |
C21 | 0.063 (3) | 0.045 (3) | 0.037 (2) | 0.007 (3) | 0.000 (3) | 0.007 (2) |
C22 | 0.066 (4) | 0.050 (4) | 0.065 (4) | 0.002 (3) | 0.010 (3) | −0.009 (3) |
C23 | 0.049 (3) | 0.075 (4) | 0.056 (3) | −0.001 (3) | 0.006 (3) | −0.005 (3) |
O1—C9 | 1.199 (7) | C8—C21 | 1.531 (7) |
O2—C7 | 1.199 (6) | C8—C9 | 1.534 (7) |
O10—C9 | 1.348 (6) | C11—C12 | 1.505 (7) |
O10—C11 | 1.461 (6) | C11—H11 | 0.9800 |
O16—C17 | 1.408 (6) | C12—C13 | 1.518 (7) |
O16—C15 | 1.432 (6) | C12—H12A | 0.9700 |
O18—C17 | 1.418 (6) | C12—H12B | 0.9700 |
O18—C19 | 1.443 (6) | C13—C14 | 1.544 (7) |
C1—C11 | 1.523 (7) | C13—H13A | 0.9700 |
C1—C20 | 1.552 (6) | C13—H13B | 0.9700 |
C1—C19 | 1.555 (7) | C14—C15 | 1.523 (7) |
C1—C2 | 1.558 (6) | C14—C23 | 1.533 (8) |
C2—C3 | 1.545 (7) | C14—C20 | 1.534 (7) |
C2—C8 | 1.575 (7) | C15—H15A | 0.9700 |
C2—H2 | 0.9800 | C15—H15B | 0.9700 |
C3—C4 | 1.539 (7) | C17—C20 | 1.536 (7) |
C3—H3A | 0.9700 | C17—H17 | 0.9800 |
C3—H3B | 0.9700 | C19—H19A | 0.9700 |
C4—C5 | 1.544 (8) | C19—H19B | 0.9700 |
C4—H4A | 0.9700 | C20—H20 | 0.9800 |
C4—H4B | 0.9700 | C21—H21A | 0.9700 |
C5—C6 | 1.492 (8) | C21—H21B | 0.9700 |
C5—C21 | 1.536 (7) | C22—H22A | 0.9300 |
C5—H5 | 0.9800 | C22—H22B | 0.9300 |
C6—C22 | 1.321 (7) | C23—H23A | 0.9600 |
C6—C7 | 1.520 (7) | C23—H23B | 0.9600 |
C7—C8 | 1.539 (7) | C23—H23C | 0.9600 |
C9—O10—C11 | 119.2 (4) | C13—C12—H12A | 109.7 |
C17—O16—C15 | 108.0 (4) | C11—C12—H12B | 109.7 |
C17—O18—C19 | 108.2 (4) | C13—C12—H12B | 109.7 |
C11—C1—C20 | 114.5 (4) | H12A—C12—H12B | 108.2 |
C11—C1—C19 | 111.3 (4) | C12—C13—C14 | 113.1 (4) |
C20—C1—C19 | 102.4 (4) | C12—C13—H13A | 109.0 |
C11—C1—C2 | 108.0 (4) | C14—C13—H13A | 109.0 |
C20—C1—C2 | 113.2 (4) | C12—C13—H13B | 109.0 |
C19—C1—C2 | 107.3 (4) | C14—C13—H13B | 109.0 |
C3—C2—C1 | 115.9 (4) | H13A—C13—H13B | 107.8 |
C3—C2—C8 | 110.2 (4) | C15—C14—C23 | 107.7 (4) |
C1—C2—C8 | 109.1 (4) | C15—C14—C20 | 102.6 (4) |
C3—C2—H2 | 107.1 | C23—C14—C20 | 109.0 (4) |
C1—C2—H2 | 107.1 | C15—C14—C13 | 113.2 (5) |
C8—C2—H2 | 107.1 | C23—C14—C13 | 109.5 (4) |
C4—C3—C2 | 113.4 (4) | C20—C14—C13 | 114.5 (4) |
C4—C3—H3A | 108.9 | O16—C15—C14 | 105.1 (4) |
C2—C3—H3A | 108.9 | O16—C15—H15A | 110.7 |
C4—C3—H3B | 108.9 | C14—C15—H15A | 110.7 |
C2—C3—H3B | 108.9 | O16—C15—H15B | 110.7 |
H3A—C3—H3B | 107.7 | C14—C15—H15B | 110.7 |
C3—C4—C5 | 113.5 (4) | H15A—C15—H15B | 108.8 |
C3—C4—H4A | 108.9 | O16—C17—O18 | 112.2 (4) |
C5—C4—H4A | 108.9 | O16—C17—C20 | 108.2 (4) |
C3—C4—H4B | 108.9 | O18—C17—C20 | 108.2 (4) |
C5—C4—H4B | 108.9 | O16—C17—H17 | 109.4 |
H4A—C4—H4B | 107.7 | O18—C17—H17 | 109.4 |
C6—C5—C21 | 101.4 (5) | C20—C17—H17 | 109.4 |
C6—C5—C4 | 112.3 (4) | O18—C19—C1 | 103.1 (4) |
C21—C5—C4 | 108.7 (4) | O18—C19—H19A | 111.2 |
C6—C5—H5 | 111.3 | C1—C19—H19A | 111.2 |
C21—C5—H5 | 111.3 | O18—C19—H19B | 111.2 |
C4—C5—H5 | 111.3 | C1—C19—H19B | 111.2 |
C22—C6—C5 | 130.8 (5) | H19A—C19—H19B | 109.1 |
C22—C6—C7 | 121.8 (5) | C14—C20—C17 | 103.8 (4) |
C5—C6—C7 | 107.3 (4) | C14—C20—C1 | 117.7 (4) |
O2—C7—C6 | 125.9 (5) | C17—C20—C1 | 103.5 (4) |
O2—C7—C8 | 128.5 (5) | C14—C20—H20 | 110.4 |
C6—C7—C8 | 105.4 (4) | C17—C20—H20 | 110.4 |
C21—C8—C9 | 108.7 (4) | C1—C20—H20 | 110.4 |
C21—C8—C7 | 101.0 (4) | C8—C21—C5 | 101.5 (4) |
C9—C8—C7 | 111.1 (4) | C8—C21—H21A | 111.5 |
C21—C8—C2 | 112.2 (4) | C5—C21—H21A | 111.5 |
C9—C8—C2 | 117.1 (4) | C8—C21—H21B | 111.5 |
C7—C8—C2 | 105.6 (4) | C5—C21—H21B | 111.5 |
O1—C9—O10 | 119.7 (5) | H21A—C21—H21B | 109.3 |
O1—C9—C8 | 123.5 (5) | C6—C22—H22A | 120.0 |
O10—C9—C8 | 116.6 (5) | C6—C22—H22B | 120.0 |
O10—C11—C12 | 107.0 (4) | H22A—C22—H22B | 120.0 |
O10—C11—C1 | 108.2 (4) | C14—C23—H23A | 109.5 |
C12—C11—C1 | 115.0 (4) | C14—C23—H23B | 109.5 |
O10—C11—H11 | 108.9 | H23A—C23—H23B | 109.5 |
C12—C11—H11 | 108.9 | C14—C23—H23C | 109.5 |
C1—C11—H11 | 108.9 | H23A—C23—H23C | 109.5 |
C11—C12—C13 | 109.9 (4) | H23B—C23—H23C | 109.5 |
C11—C12—H12A | 109.7 | ||
C11—C1—C2—C3 | 82.7 (5) | C2—C1—C11—O10 | 71.0 (5) |
C20—C1—C2—C3 | −45.1 (5) | C20—C1—C11—C12 | −42.5 (6) |
C19—C1—C2—C3 | −157.3 (4) | C19—C1—C11—C12 | 73.0 (5) |
C11—C1—C2—C8 | −42.3 (5) | C2—C1—C11—C12 | −169.5 (4) |
C20—C1—C2—C8 | −170.1 (4) | O10—C11—C12—C13 | 177.5 (4) |
C19—C1—C2—C8 | 77.7 (4) | C1—C11—C12—C13 | 57.4 (6) |
C1—C2—C3—C4 | −169.3 (4) | C11—C12—C13—C14 | −58.3 (6) |
C8—C2—C3—C4 | −44.8 (6) | C12—C13—C14—C15 | −71.9 (6) |
C2—C3—C4—C5 | 39.5 (6) | C12—C13—C14—C23 | 168.0 (5) |
C3—C4—C5—C6 | −91.0 (6) | C12—C13—C14—C20 | 45.3 (6) |
C3—C4—C5—C21 | 20.4 (6) | C17—O16—C15—C14 | −34.5 (5) |
C21—C5—C6—C22 | 149.2 (6) | C23—C14—C15—O16 | −81.1 (5) |
C4—C5—C6—C22 | −95.0 (6) | C20—C14—C15—O16 | 33.8 (5) |
C21—C5—C6—C7 | −28.9 (5) | C13—C14—C15—O16 | 157.7 (4) |
C4—C5—C6—C7 | 86.9 (5) | C15—O16—C17—O18 | −98.7 (5) |
C22—C6—C7—O2 | 6.0 (8) | C15—O16—C17—C20 | 20.6 (5) |
C5—C6—C7—O2 | −175.7 (5) | C19—O18—C17—O16 | 95.5 (5) |
C22—C6—C7—C8 | −177.4 (5) | C19—O18—C17—C20 | −23.9 (5) |
C5—C6—C7—C8 | 0.9 (5) | C17—O18—C19—C1 | 37.8 (5) |
O2—C7—C8—C21 | −156.0 (6) | C11—C1—C19—O18 | −158.8 (4) |
C6—C7—C8—C21 | 27.5 (5) | C20—C1—C19—O18 | −36.1 (5) |
O2—C7—C8—C9 | −40.9 (7) | C2—C1—C19—O18 | 83.3 (4) |
C6—C7—C8—C9 | 142.6 (4) | C15—C14—C20—C17 | −20.9 (5) |
O2—C7—C8—C2 | 87.0 (6) | C23—C14—C20—C17 | 93.1 (5) |
C6—C7—C8—C2 | −89.5 (4) | C13—C14—C20—C17 | −143.9 (5) |
C3—C2—C8—C21 | −9.1 (6) | C15—C14—C20—C1 | 92.7 (5) |
C1—C2—C8—C21 | 119.2 (4) | C23—C14—C20—C1 | −153.3 (4) |
C3—C2—C8—C9 | −135.8 (5) | C13—C14—C20—C1 | −30.3 (6) |
C1—C2—C8—C9 | −7.5 (6) | O16—C17—C20—C14 | 1.4 (5) |
C3—C2—C8—C7 | 100.0 (5) | O18—C17—C20—C14 | 123.2 (4) |
C1—C2—C8—C7 | −131.7 (4) | O16—C17—C20—C1 | −122.1 (4) |
C11—O10—C9—O1 | 176.3 (5) | O18—C17—C20—C1 | −0.3 (5) |
C11—O10—C9—C8 | −8.0 (6) | C11—C1—C20—C14 | 28.6 (5) |
C21—C8—C9—O1 | 82.9 (7) | C19—C1—C20—C14 | −91.9 (4) |
C7—C8—C9—O1 | −27.3 (7) | C2—C1—C20—C14 | 152.9 (4) |
C2—C8—C9—O1 | −148.7 (5) | C11—C1—C20—C17 | 142.4 (4) |
C21—C8—C9—O10 | −92.6 (5) | C19—C1—C20—C17 | 21.8 (5) |
C7—C8—C9—O10 | 157.1 (4) | C2—C1—C20—C17 | −93.3 (4) |
C2—C8—C9—O10 | 35.8 (6) | C9—C8—C21—C5 | −162.2 (4) |
C9—O10—C11—C12 | −169.4 (4) | C7—C8—C21—C5 | −45.3 (5) |
C9—O10—C11—C1 | −45.0 (5) | C2—C8—C21—C5 | 66.7 (5) |
C20—C1—C11—O10 | −162.0 (4) | C6—C5—C21—C8 | 46.3 (5) |
C19—C1—C11—O10 | −46.5 (5) | C4—C5—C21—C8 | −72.2 (5) |
Experimental details
Crystal data | |
Chemical formula | C20H24O5 |
Mr | 344.39 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 298 |
a, b, c (Å) | 7.845 (1), 13.1365 (17), 16.178 (2) |
V (Å3) | 1667.2 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.20 × 0.18 × 0.13 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 1999) |
Tmin, Tmax | 0.981, 0.987 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7324, 1707, 1158 |
Rint | 0.151 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.062, 0.159, 0.99 |
No. of reflections | 1707 |
No. of parameters | 228 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.27, −0.23 |
Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003).
Ring | Q, Å | θ,° | φ,° |
A | 0.478 (5) | 24.8 (6) | 126.4 (14) |
B | 0.664 (5) | 106.1 (4) | 89.3 (4) |
C | 0.821 (5) | 100.1 (3) | 54.3 (4) |
Q2, Å | φ2, ° | ||
D | 0.473 (5) | 324.5 (6) | |
E | 0.365 (5) | 321.7 (7) | |
F | 0.330 (5) | 140.1 (9) |
Acknowledgements
This project was supported by the Natural Science Foundation of Zhejiang Province, China (grant No. Y205318).
References
Bruker (1999). SMART (Version 5.611), SAINT (Version 6.02a) and SADABS (Version 2.08). Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358. CrossRef CAS Web of Science Google Scholar
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany. Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wang, Z. Q., Wang, X. R., Dong, J. G. & Xue, Z. W. (1986). Acta Bot. Sin. 28, 79–85. CAS Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The diterpenoid macrocalyxoformin B, (I), has been previously isolated from Rabdosia macrocalyx Hara (Wang et al., 1986) and its structure was established from the spectroscopic and chemical evidence. Recently, it was for the first time isolated from Rabdosia var lophanthoides Hara, and its structure was confirmed by an X-ray diffraction study.
The molecule is built up from six fused rings, three six membered and three five membered rings (Fig. 1). Some geometrical features of these rings were investigated using PLATON (Spek, 2003).
Cyclohexane ring A (C1/C11—C14/C20) adopts a chair conformation (Cremer & Pople, 1975), ring B (O10/C9/C8/C2/C1/C11) exists in a screw-boat conformation, ring C (C2—C5/C21/C8) adopts the boat conformation. All the three five-membered rings adopt envelope conformation.